Electronic module having a groove anchoring terminal pins

Abstract

A module has electronic components mounted to a Printed Circuit Board (PCB) with multiple patterned conductive layers connecting to conductive slot metal around a conductive slot. A groove is cut through a top molding encapsulant above and into the conductive slot but does not cut through a bottom molding encapsulant. A terminal pin is inserted into the groove and pushed down into the conductive slot. When heated, embedded solder previously applied to the conductive slot metal flows between the end of the terminal pin and the conductive slot metal to form a solder bond. An end of the PCB past the conductive slot has no metal traces, preventing shorts. Epoxy can be placed into the groove around the terminal pin or a hole formed in the terminal pin to increase strength of the anchored terminal pin. The molding around the groove protects terminal pins from shorting from the side.

Description

FIELD OF THE INVENTION[0001]This invention relates to electronic device packaging, and more particularly to modules with anchored terminal pins.BACKGROUND OF THE INVENTION[0002]Semiconductor devices such as Integrated Circuits (ICs) are individually encapsulated in rigid plastic or ceramic and provided with leads, solder balls, or pins for making electrical connection. Various modules having more than one IC are also available. Some modules may contain several encapsulated IC's along with other components such as resistors, capacitors, and inductors, all mounted on a small substrate such as a Printed Circuit Board (PCB).[0003]FIG. 1 shows a prior-art module with side pins. Module 10 may be a small PCB with electronic components such as IC's, resistors, capacitors, etc. mounted thereon and surrounded by an encapsulant such as rigid plastic. Terminal pins 18 are attached to the edge of this PCB to provide electrical connection to wiring traces on the module's PCB. Terminal pins 18 may...

AI Technical Summary

Problems solved by technology

Even if terminal pin 18 does not completely break off, there may be cracks formed in the solder connection or in other parts of module 10 that can cause reliability problems.

Also, when module 10 is attached to a larger PCB such as a motherboard, or inserted into a socket or into holes in a PCB, the insertion force exerted on terminal pin 18 may cause cracks in the solder connection to metal pad 92 resulting in reliability problems.

Another problem is that the sides of terminal pins 18 are exposed and may make electrical contact with other components, resulting in shorting.

When module 10 is a power device generating high voltages and currents, such shorting may be dangerous and result in damage and accidental electrocution.

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